Why are food shortages not listed as a risk in the National Risk Register?

Report by Sam Hilton, Sahil Shah
Published on 05 August 2021

Sam Hilton, Research Affiliate at the Centre for the Study of Existential Risk, University of Cambridge

Sahil Shah, specialist researcher on food security, ALLFED and Jahn Research


The UK government is reviewing how the National Security Risk Assessment (NSRA) works in order to learn the lessons from COVID-19.

There are serious risks that could affect the UK that are not included in the 2020 National Risk Register (NRR). One such risk is food shortages – this briefing looks at why it is not mentioned.

We suggest that it is not mentioned in the NRR because:

  1. “Disruption to food supplies” is classified as a shared consequence of various risks in the NSRA rather than a risk in its own right.
  2. The NSRA does not focus on exploring and capturing all risks, especially high-uncertainty and high-impact risks.

We discuss how this likely leads to the UK being underprepared for food shortages and potentially other risks.


The 2020 National Risk Register (NRR) describes itself as “the public-facing version of the National Security Risk Assessment (NSRA) – a classified cross-government and scientifically rigorous assessment of the most serious risks facing the UK”. The register then provides details on a range of risks that could affect the UK. It is however possible that there are serious risks to the UK which are not listed in the NRR (or the NSRA).

One apparent possible omission is a food supply or distribution crisis, which is not mentioned in the NRR. Small food supply shocks and resultant price rises are fairly common, there have been small food price rises in both 2007-08 and 2010-12. A large- scale food supply shock might be a risk deserving of concern and government attention.

This report looks at large-scale food supply shocks. It looks at the scale of the risk, considers why it is not mentioned in the NRR and discusses the implications of this for UK food security and UK risk management more generally.

The food security risk

What is the risk? A severe weather anomaly (e.g. heat wave in the UK), supply chain disruption or other risk factor may lead to food shortages in the UK. An extreme global scenario (e.g. several extreme weather events) could lead to a multiple bread basket failure (MBBF) and a 10% global food deficit (loss of calorie production) or worse. A deficit of less than 1% caused the 2007-08 food price spike. A 5-10% food deficit in 1816-18 led to millions of deaths across Europe, America and Asia. A food system shock scenario, published by Lloyds of London, envisages food price increases of up to 500%, urban food riots and a million deaths.

How likely is this risk? Research commissioned by the UK Foreign and Commonwealth Office (FCO) suggests that an MBBF leading to a 10% global food deficit is roughly 1 in 200 chance annually, and rising significantly over future years. The report only considers food shocks as a result of extreme weather events yet there are other possible causes of extreme food shortages in the UK, including: loss of port functions, cascading scenarios, agroterrorism, volcanic events, and conflict.

Can this risk be effectively prepared for? Improving resilience to food shock risks is cheap, with many plausible actions that could be taken within the £1-10m cost range. Good planning is relatively cheap and (as set out in the Integrated Review, p88, and various other sources) is necessary to build resilience. In this case plans could be made to scale up food production or introduce rationing in a disaster scenario. Investments in closed-food systems is another approach that can mitigate the risk and could likely be funded from existing research budgets.

Possible explanations for this risk not being in the NRR

Given the scale of the risk it is worth considering why it is not mentioned in the NRR. There are a five reasons that we can identify, likely some amount of all of these factors play a part:

  1. The NSRA divides the topics it considers into “risks” and “risk consequences”. So “disruption to food supplies” is listed in the 2018 NSRA as a shared consequence of many risks, but not as a risk in and of itself. By virtue of being a shared consequence of many scenarios, food security may be under-emphasised in the NSRA and is entirely excluded from the NRR.
  2. Risk assessors may have decided the risk was too low-probability to list in the NSRA. The analysis above of the likelihood of food price shocks and of an MBBF could certainly be overly pessimistic. Even so there are still a few reasons to be cautious that a decision not list food shortages would be warranted:
    1. Not listing this risk would be putting significant weight on highly speculative likelihood estimates, which could easily be wrong by orders of magnitude.
    2. Low-probability risks that are also high-impact, such as a large-scale food shortage, may be worth preparing for.
    3. The NSRA only looks two years ahead but this is a risk that appears to be growing rapidly, and it may be worth preparing for it sooner rather than later.
  3. Foresight work should involve both exploration and of potential futures and prediction of what those futures may look like. The NSRA process may be failing to sufficiently explore as well as predict the scope of risks. The UK government does do horizon scanning and does add new risks to the NSRA, such as space weather (added in 2011). However the current horizon scanning and expert engagement processes relies largely on domain specific teams so may not be sufficiently exploratory.
  4. UK risk assessors may be looking back at how the UK managed food shortages in WW2, where the issue was well managed and a specialised food ministry was put in place early. This risks ignoring the lessons of 1816 and earlier large-scale food shortages. Countries with a living memory of famine (Netherlands, China, India) tend to put more work into this issue. This matches a pattern of Government risk assessors focusing on data from recent risk events. For example, pandemic estimates were based on events in the relatively recent past, notably Spanish flu in 1918, SARS in 2002, and Ebola in 2013, rather than historical events such as Cholera pandemics in the 1800s or various plague epidemics.
  5. A lack of pressure from outside government. Agriculture academics and supply chain professionals may be confident that the UK can cope with “all usual challenges” (which is true) but not be focused on the tail risks.


How concerning is this for the UK’s food security?

That food shortage risks are not included in the NRR and are only treated as a shared consequence by the NSRA is problematic. The risk appears to be high-impact and low-medium likelihood (compared to other risks listed in the NSRA) and cheap to prepare for. The UK government should explain why the risk is not listed and how it plans to prepare for large scale food shortages, MBBFs and food deficits of 10%+. 

How concerning is this beyond just food security?

This highlights two areas of concern regarding how the UK identifies national disaster risks:

  • The UK may underfocus on the shared consequences of risks, where those shared consequences may be both high-impact and reasonably likely to occur. The division between risk and risk consequences is somewhat arbitrary and yet the UK appears to preference risks rather than consequences. Shared consequences of risks are not listed in the NRR to support local risk planning, and it is not clear that central government departments are assigned ownership of shared consequences of risks.
  • The UK’s risk identification process may not be mapping out the full range of risks to the UK. The UK may be insufficiently building resilience for or preparing for high-uncertainty high-impact risks, even when such preparedness is low cost. The UK may be failing to explore the full range of possible risks. This matches a pattern of risks being added to the NSRA only after they impacted the UK: volcanic risk was added after the 2010 and 2011 Icelandic eruptions and mis-information risk was added after the “Russia Report” and attacks on 5G towers highlighted the issue.


It should be noted that despite the above concerns, on the whole, the UK’s National Security Risk Assessment does an adequate job of identifying the vast majority of the risks to the UK.

Nevertheless, we welcome the UK government’s commitment to “review our approach to risk assessment" in the Integrated Review (page 91). Flaws in the design of the NSRA which lead to risks such as food security not being included are serious problems and we hope the government addresses them in its review. 

Finally, although this note focuses on the specifics of risk identification, readers should be mindful that other work in this space highlights a range of different areas for improvement. For example, the Institute for Government’s analysis, and our ‘Risk management in the UK’ paper, both highlight the general challenge of ensuring that the NSRA process feeds into cross-government risk preparedness and risk planning.

To be introduced to experts on this issue, who can provide more specific recommendations, tailored research, and implementation advice, please contact the Centre for Long-Term Resilience or Sam Hilton

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